The 42nd Infantry Division was an infantry division of the British Army. The division was raised in 1908 as part of the Territorial Force (TF), originally as the East Lancashire Division, and was redesignated as the 42nd Division on 25 May 1915. It was the first TF division to be sent overseas during the First World War. The division fought at Gallipoli, in the Sinai desert and on the Western Front in France and Belgium. Disbanded after the war, it was reformed in the Territorial Army (TA), in the Second World War it served as the 42nd Infantry Division with the British Expeditionary Force (BEF) and fought in Belgium and France before being evacuated at Dunkirk. The division was later reformed in the United Kingdom and, in November 1941, was converted into the 42nd Armoured Division, which was disbanded in October 1943 without serving overseas. A 2nd Line duplicate formation, the 66th Division, was created when the Territorials were doubled in both world wars.
The 54th Infantry Division was an infantry division of the British Army. The division was raised in 1908 following the creation of the Territorial Force (TF) as the East Anglian Division. During the First World War the division fought at Gallipoli and in the Middle East. The division was disbanded after the war but reformed in the Territorial Army in 1920. During the Second World War it was a home service division and did not see any combat service abroad and was disbanded in late 1943 but many of its component units went to see service in the Normandy Campaign and North-western Europe from June 1944 to May 1945.
The 4th Infantry Division was a regular infantry division of the British Army with a very long history, seeing active service in the Peninsular War, the Crimean War, the First World War, and during the Second World War. It was disbanded after the war and reformed in the 1950s as an armoured formation before being disbanded and reformed again and finally disbanded on 1 January 2012.
The 54th Infantry Brigade was an infantry brigade of the British Army that saw active service in both the First and Second World Wars.
The 36th Infantry Brigade was an infantry brigade formation of British Army that fought in the First World War, as part of 12th (Eastern) Division, on the Western Front. The brigade also fought in the Second World War, with the 12th (Eastern) Infantry Division, in France, and later with 78th Infantry Division in Tunisia and Italy.
The 145th Infantry Brigade was a regional brigade of the British Army that saw active service in both the First and the Second World Wars, disbanding in 1943 and being reformed in the 1990s. The Brigade was renamed Headquarters 11th Infantry Brigade and Headquarters South East in October 2014.
The 71st Infantry Brigade was an infantry brigade formation of the British Army that saw active service during both the First and Second World Wars.
The 158th Infantry Brigade was an infantry brigade of the British Army that served in both the First and Second World Wars, before being disbanded in 1968. Throughout its existence the brigade was assigned to the 53rd (Welsh) Infantry Division and was composed almost entirely of Territorial battalions from the Royal Welch Fusiliers.
The 125th Brigade was an infantry brigade formation of the British Army that saw active service during both the First and Second World Wars. It was assigned to the 42nd Division and served in the Middle East and later in the trenches of the Western Front in the First World War. In the Second World War the brigade, now redesignated 125th Infantry Brigade, fought in Belgium and France before being evacuated at Dunkirk and was then converted into 10th Armoured Brigade.
The 126th Brigade was an infantry brigade of the British Army during the First World War and the Second World War. It was assigned to the 42nd Division and served in the Middle East and on the Western Front in the Great War. In the Second World War, now as the 126th Infantry Brigade, it served again with the 42nd Division in France and was evacuated at Dunkirk and then later converted into 11th Armoured Brigade.
The 155th Brigade was an infantry brigade of the British Army that saw active service in both the First and the Second World Wars. Assigned to the 52nd (Lowland) Division, the brigade saw active service in the Middle East and on the Western Front during the First World War. During the Second World War, now the 155th Infantry Brigade, it continued to serve with the 52nd Division in Operation Dynamo, and later in North-western Europe from late 1944 until May 1945.
The 164th Brigade was an infantry brigade of the British Army that saw active service in the First World War as part of the 55th Division. As the 164th Infantry Brigade, it remained in the United Kingdom throughout the Second World War, as part of the 55th Infantry Division.
The 166th Brigade was an infantry brigade of the British Army that saw active service in the First World War and remained in the United Kingdom throughout the Second World War.
The 45th Infantry Brigade was an infantry brigade of the British Army that saw active service in both the First and the Second World Wars with 15th (Scottish) Infantry Division.
The 197th Brigade was an infantry brigade formation of the British Army that saw distinguished active service in both the First and Second world wars.
The 199th Brigade was an infantry brigade formation of the British Army that saw active service during the First World War as part of 66th Division and was reformed as 199th Infantry Brigade in the Second World War, serving with 55th Infantry Division until August 1944 when it was redesignated 166th Infantry Brigade.
The 113th Brigade was an infantry brigade formation of the British Army active in both the First and the Second World Wars.
The 66th Division was an infantry division of the British Army, part of the Territorial Force, which saw service in the trenches of the Western Front, during the later years of the Great War and was disbanded after the war.
The 176th Brigade was an infantry brigade of the British Army that saw active service in the First World War on the Western Front and disbanded in 1919. The brigade was raised again, now known as 176th Infantry Brigade, shortly prior to the Second World War and fought in the Normandy Campaign before being disbanded in August 1944. In both world wars the brigade was assigned to a 59th Division: the 59th Division during the first, and the 59th (Staffordshire) Infantry Division in the second.
The 144th Infantry Brigade was an infantry brigade of the British Army that saw active service in the First World War and again in the early stages of the Second World War before being reduced to a reserve brigade and remained in the United Kingdom for the rest of the war. In both world wars the brigade served with 48th Division.
United Kingdom 
Territorial Army